Coloring matters



Patented May 25, 1937 NITED-STAT S PATENT OFFICE I COLORING MATTERS g VCyril Child and Harry. Augustus Thomas, Black- I ley, Manchester,England,,assignors to 1111- perial Chemical Industries Limited, acorporation -of GreatBritain No Drawing. Application June 4, 1935,Serial No. 24,983. In Great Britain June :8, 1934.

Claims. (0118- 6) This invention relates to the preparation of asolution of 200 parts of glucose in 180 parts of stable coloredcolloidal solutions from vat dye water, giving a total of 3800 parts ofsolution stuffs. having a pH value of approximately 10.

.By vat dyestuffs we mean that class of dyes '30 parts of this solutionare added to 1500 parts 5 which aredyed from alkaline hydrosulfite vats,of. an aqueous solution of sodium hydrosulfit'e 5 such as .indigoid andanthraquinone vat dye and sodium hydroxide solution inwhich the stuffs,dyestuffs of the I-Iydron Blue class, etc. anthraquinone vat dyestuff,Caledon Blue RC When Wool or other animal proteid material (Colour IndexNo. 1114) is then dissolved by reorwheat starch gluten, or other complexamino duction at 50 .,C., in the following proportions:

10 acid bodies are immersed'in aqueous caustic 100 par-ts of a 5%aqueous suspension of thevat 10 alkali, imbibition of alkali and watertakes place, dyestuff to 3.75 parts of sodium hydrosulfite in followedby swelling and eventual solution of the 45 parts of 20% aqueous sodiumhydroxide soluniaterialtion. We have found that if a vat dyestuffbevatted After standing for some hours, the deep blue in the presence ofthe said dissolved material solution does not exhibit reducingproperties 15 and then oxidized, a homogeneous colored liquid towardseasily reducible vat dyestuffs, and is quite is obtained whichreadilypasses through filter stable and filterable through filter paper.

paper and which can be diluted with water to "The solution can bediluted freely with cold any extent. water to give a clear pale bluesolutionwith H The dissolving of the proteid material and which cottonfabric can be evenly tinted by im- 20 the vatting may be donesimultaneously in the mersion, followed by drying.

same liquor. Alternatively, animal fiber dyed Emampzeg 2 with the vatdyestuff maybe used asstarting 1 material instead of a proteid:substance and a 50 parts of cross-bred wool slubbing are dyed vat.dyestuff separately; in this case it is not at 50 C. for half an hourwith of the annecessary to revat the dyestuff. These solutionsthraquinone vat dyestufi", Caledon Blue GCP may be acidified, in whichcase, if sufiicientacid (Colour Index No.. .11-13), from 1500 parts ofis present, an insoluble gel separates. This can liquor containing 28parts of 76 Tw. aqueous be isolated and mixed with alkali, when a pastesodium hydroxide solution and 12 parts of so- 0 is obtained which isredispersible with water to dium hydrosulfite and in which the vat color30 form a colloidal solution, similar in properties hasbeen previouslydissolved by reduction at to that above described. I I 50 C. I

The colloidal solutions are of wide applica- .The shade on the dyed woolis allowed to detion for coloring purposes in trades such as those velopby atmospheric oxidation and the wool is relating to textiles, paper andrubber. 1

T y y, for exa p be used for t n hydroxide solution by immersing at16-18 C. for fabrics, for instance, for improving the white- 18v hoursand finally. stirring at 50 C. for 1 ness of bleached fabrics it" isthen advantageous hour. 1.5 parts of the wetting agent which can to adda small amount of a wetting-out agent be ob taine d according to U. S.P, 1,836,428 are then dissolved in 500 parts of 8% aqueous sodium 35" 40such as n b obtai d according t s then dissolved in the solution. Theresulting 4 0 deep blue solution can be poured into a large bulk of coldwater to give a stable clear pale blue solution.

1,836,428. They may also be used in dyeing paper pulp in the beater.

The following examples, in which parts are by weight, illustrate but donot limit the inven- Example 3 45 tion. parts of cross-bred woolslubbing are dyed Example; 1 at 50 C. for half an hour with 30% of theindigoid vat dyestuff, Durindone Red 3B (Colour 200 Parts of botany W001Slubbmg a Index No. 1212), and which has been previously Solved 9 PartsP 5% l 5001mm. dissolved by vatting at '70-s0 c. in parts of droxldesolution by immersing w1th occasional a solution f 5 parts of sgdiumhydr sulfite stirring for 24 hours at 16-20 C. 1000 parts of and 13parts of a 76 Tw. aqueous solution of 1 aq Sulfuric acid 50111111011 arethen sodium hydroxide and 5 parts of Turkey red oil. stirred into thesolution, followed by 220 parts After the shade has been allowed todevelop, 55 of 10% aqueous sodium hydroxide solution and the dyed Woolis dissolved as described previ- 55 ously to give a deep red stablesolution. This solution can be well mixed with a rubber latex emulsionfrom which homogeneously colored rubber can be obtained.

Ewwmple 4 The anthraquinone dyestuff, Caledon Blue GC (Colour Index No.1115), is dissolved at 50 C. in aqueous alkaline hydrosulfite solutionmade up from 100 parts of a 5% aqueous suspension of the dyestuff, 3.75parts of sodium hydrosulfite and 45 parts of a 20% aqueous sodiumhydroxide solution in 1500 parts of water, and also containing 50 partsof a 5% solution of wheat flour gluten in aqueous sodium hydroxide of pH11.

The deep blue solution obtained after atmospheric oxidation is quitestable and is miscible with water in all proportions. Acidificationprecipitates the deeply blue colored gluten products in a colloidalform, leaving an almost colorless liquor.

Example 5 50 parts of wool slubbing dyed as described in Example 2 with30% of the anthraquinone vat dyestuff, Caledon Gold Orange G (ColourIndex No. 1096), are dissolved in 500 parts of 8%, aqueous sodiumhydroxide solution. An orange colored solution is obtained which ismiscible with water in all proportions giving clear stable solutions.

Example 6 I 50 parts of the indigoid vat dyestuff, Durindone Blue 43C(Colour Index No. 1184), are mixed with 656 parts of a 5% solution ofwool substance in 5% aqueous sodium hydroxide, and vatted at 60 C.- withthe addition of 15 parts of sodium hydrosulfite and a solution of 18parts of sodium hydroxide in 350 parts of water. After 1 hour at 60 C.the dark liquor is neutralized with 90 parts of 25% aqueous sulfuricacid while agitating, when the liquor assumes the bright blue shade ofthe oxidized dyestufi. The liquor is then made acid. If sufficientlyacid a colloidal vat dye gel is precipitated and this may be isolated byfiltering through cloth. It is washed with water, and if pasted withaqueous sodium hydroxide, disperses readily in water to give a colloidalsolution suitable for padding cotton or linen cloth. The paste is alsoeminently suitable for coloring paper pulp in the beater.

Instead of isolating the collidal vat dye mixture, the slightlyacidified liquor containing the bright blue oxidized vat dye and woolsubstance can be vigorously agitated with 35 parts of aqueous sodiumhydroxide of 76 Tw., when a deep blue solution is obtained, which can bediluted with water and. passes through Whatman No. 1

filter paper, without loss in tinctorial strength; This solution can beemployed for tinting cotton or linen.

We claim:

1. A stable colored colloidal solution of a vat dyestuff comprising avat dyestuff in an aqueous alkaline solution of wool.

2. A stable colored colloidal solution of a leuco vat dyestuff in anaqueous alkaline solution of wool.

3. In the preparation of stable colored colloidal solutions of vatdyestuffs, the step which comprises incorporating a vat dyestufi in anaqueous alkaline solution containing wool dissolved therein.

4. In the preparation of stable colored colloidal solutions of vatdyestuffs, the step which comprises incorporating a vat dyestufi inleuco form in an aqueous alkaline solution containing wool dissolvedtherein.

5. In the preparation of stable colored colloidal solutions of vatdyestuffs, the steps which comprise dyeing wool fiber from an alkalinehydrosulfite solution of the dyestufi and dissolving the resulting wooland dyestufi in an alkaline solution, acidifying the solution andisolating the resulting colloidal vat dye gel.

6. In the preparation of stable colored colloidal solutions of vatdyestuffs, the steps which comprisev dyeing wool fiber from an alkalinehydrosulfite solutiton of the dyestuff and dissolving the resulting wooland dyestufi in an alkaline solution, acidifying the solution, isolatingthe resulting colloidal vat dye gel and pasting the said gel in anaqueous alkaline solution.

'7. In the preparation of stable colored colloidal solutions of vatdyestuffs, the steps which comprise incorporating a vat dyestuff inleuco form in an aqueous alkaline solution of wool, acidifying thesolution, isolating the resulting colloidal vat dye gel and pasting saidgel in an aqueous alkaline solution.

8. In the preparation of stable colored colloidal solutions of vatdyestuffs, the steps which comprise adding to an alkaline solution ofwool a vat dyestufi, vatting the dyestufi by the addition of sodiumhydrosulfite, oxidizing the resulting leuco compound in the solution,acidifying the solution and isolating the resulting colloidal vat dyegel.

9. In the preparation of stable colored colloidal solutions of vatdyestuffs, the steps which comprise dissolving wool in an aqueoussolution of an alkali and incorporating therewith an alkaline solutionof a vat dyestufi in leuco form.

10. An isolated stable colored colloidal vat dye gel obtainable by theprocess of claim 5.

CYRIL CHILD. HARRY AUGUSTUS THOMAS.

